Diff: main.cpp

Revision:

0:a0204dfc42fd

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Thu Sep 09 15:43:12 2010 +0000
@@ -0,0 +1,157 @@
+/*
+Heart Beat Monitor v1.0 w/ BlueBeat(Java-based program for mobile phones) & BlueBeat for PC
+Authors: Dejan Volk & Blaz Magdic
+3rd grade of Computer Science, Faculty of Electrical Engineering and Computer Science
+Maribor, Slovenia
+
+Used for sending information about heart beats per minute to the mobile phone via
+Bluetooth module WT11-A-AI made by Bluegiga.
+
+Description of pins used:
+
+p5 - RESET switch for Polar's RMCM01 OEM module
+p8 - RESET switch on WT11
+p9 - TX for communicating with WT11
+p10 - RX for communicating with WT11
+p11 - DigitalIn for Polar's RMCM01 OEM module (pin HR)
+p12 - DigitalIn for Polar's RMCM01 OEM module (pin FPLS)
+
+Possible improvements:
+- Integrating a LCD monitor that will use the serial port to display information about the current heart beat
+- Implementing a more efficient algorithm to calculate the heart beat
+- Better code comments (doh)
+
+*/
+
+#include "mbed.h"
+
+//************global declarations*****************
+Serial s_port(p9,p10);
+DigitalOut led_yes(LED1); //visual indicator for sending data to WT11
+DigitalOut reset(p8);  //reset trigger on WT11
+DigitalOut reset_RMCM(p5);    //reset trigger on RMCM01
+InterruptIn heartBeat(p12);
+Timer timer;
+int interval;    //interval between heartbeats
+int intrHB;      //heartbeats per minute
+int baud_rate = 115200;
+int bits = 8;
+int stop_bits = 1;
+int counter_HB = 0;
+int array[3];        //small array for storing heart beats
+bool intrPin = false;
+int previous = 11;    //variable that stores the previously calculated heartbeat
+//***********end of global declarations*************
+
+void initWT11() {       //init function for initial configuration of WT11 module
+    int zero = 0;
+    int high = 1;
+    reset.write(zero); //Initializing WT11 for inputting commands
+    wait(0.2);
+    reset.write(high);
+    wait(0.01);
+    reset.write(zero);
+    wait(2);
+    //Configuration for WT11 - setting it to slave mode
+    s_port.printf("SET BT PAGEMODE 3 2000 1\n");
+    s_port.printf("SET BT NAME HBMWT11\n");
+    s_port.printf("SET BT ROLE 0 f 7d00\n");
+    s_port.printf("SET CONTROL ECHO 0\n");
+    s_port.printf("SET BT AUTH * 1234\n");
+    s_port.printf("SET CONTROL ESCAPE 43 00 0\n");
+    s_port.printf("SET CONTROL CD 00 0\n");
+    s_port.printf("SET CONTROL BAUD 115200,8n1\n");
+}
+
+void initRMCM() { //init function for initial configuration of RMCM01
+    int zero = 0;
+    int high = 1;
+    reset_RMCM.write(high);
+    wait(0.1);
+    reset_RMCM.write(zero);
+    wait(0.1);
+    reset_RMCM.write(high);
+}
+
+void intrTrigRise() {
+    led_yes=1;    //triggering the indicator led
+    interval=timer.read_ms();    //reads the interval
+    timer.stop();
+    timer.reset();          //resets the timer
+    timer.start();          //starts the timer
+    intrPin = true;        //sets the interrupt to true
+    heartBeat.mode(PullNone);
+    wait(0.29);
+    heartBeat.mode(PullUp);
+}
+
+void interpolation() {
+    if (interval != 0) {  //avoiding divide-by-zero error
+        array[counter_HB] = interval;
+        counter_HB++;
+        led_yes=0;
+
+        if (counter_HB == 3) {     //when the array is full, start calculating the average heartbeat
+            counter_HB = 0;
+            int minute = 60000;
+            int avrg = 0;
+            int temp = 0;
+            int flag = 1;
+            int avg = 0;
+
+            for (int i = 1; i <= 3 && flag; i++) {    //bubble sort in descending order
+                flag = 0;
+
+                for (int j = 0; j < 2; j++) {
+                    if (array[j+1] > array[j]) {
+                        temp = array[j];
+                        array[j] = array[j+1];
+                        array[j+1] = temp;
+                        flag = 1;
+                    }
+                }
+            }
+
+            int sum1 = (60000/array[0]) - (60000/array[1]);        //taking the middle value and calculate the difference
+            int sum2 = (60000/array[2]) - (60000/array[1]);        //between both remaining values
+
+            if ((sum1 >= -10 || sum1 <= 10) || (sum2 >= -10 || sum2 <= 10)) {        //if all values do not deviate by +/- 10 heart beats
+                for (int i = 0; i < 3; i++) {                                        //then take all 3 and calculate the average
+                    avrg+=array[i];
+                }
+                avg = avrg/3;
+            } else if ((sum1 >= -10 || sum1 <= 10) || (sum2 > 10 || sum2 < -10)) { //if 2nd sum deviates for more than +/- 10 heartbeats
+                avrg = array[0] + array[1];                                        //take the elements of 1st sum
+                avg = avrg/2;
+            } else if ((sum1 < -10 || sum1 > 10) || (sum2 <= 10 || sum2 >= -10)) { //if 1st sum deviates for more than +/- 10 heartbeats
+                avrg = array[2] + array[1];                                        //take the elements of 2nd sum
+                avg = avrg/2;
+            } else {
+                avg = previous;        //if all 3 values deviate for more than -/+ 10 heart beats, discard all and show the previous 
+            }                          //"good" heartbeat
+
+
+            intrHB = minute/avg;    //interpolating the interval to 1 min
+            intrPin = false;            //setting the interrupt to false
+            s_port.printf("#%i*",intrHB);
+            previous = avg;
+        }
+        intrPin = false;
+    } else
+        intrPin=false;
+}
+
+int main() {
+    initRMCM();                            //calling init function for RMCM01
+    s_port.baud(baud_rate);
+    s_port.format(bits,Serial::None,stop_bits);
+    initWT11();                         //calling the init function for setting WT11
+    s_port.printf("SELECT 0\n");        //switching from COMMAND mode to DATA mode
+
+    while (1) {
+        heartBeat.rise(&intrTrigRise);    //trigger for interrupt
+        if (intrPin == true && interval != 0) {  //if interrupt is true and interval is not 0, send data
+            interpolation();
+        }
+    }
+}